Search Results

Search found 35513 results on 1421 pages for 'java interfaces'.

Page 331/1421 | < Previous Page | 327 328 329 330 331 332 333 334 335 336 337 338  | Next Page >

  • java random percentages

    - by erw
    I need to generate n percentages (integers between 0 and 100) such that the sum of all n numbers adds up to 100. If I just do nextInt() n times, each time ensuring that the parameter is 100 minus the previously accumulated sum, then my percentages are biased (i.e. the first generated number will usually be largest etc.). How do I do this in an unbiased way?

    Read the article

  • Class.getArrayType in Java?

    - by ???
    I use the following trick to get the array type of a specific class: @SuppressWarnings("unchecked") public static <T> Class<T[]> getArrayType(Class<T> componentType) { String arrayClassName = "[L" + componentType.getName() + ";"; try { return (Class<T[]>) Class.forName(arrayClassName); } catch (ClassNotFoundException e) { throw new UnexpectedException("Can't get the array type for " + componentType, e); } } But, is there any more elegant way to get this?

    Read the article

  • ByteArrayOutputStream to PrintWriter (Java Servlet)

    - by Thomas
    Writing generated PDF (ByteArrayOutputStream) in a Servlet to PrintWriter. I am desperately looking for a way to write a generated PDF file to the response PrintWriter. Since a Filter up the hierarchy chain has already called response.getWriter() I can't get response.getOutputStream(). I do have a ByteArrayOutputStream where I generated the PDF into. Now all I need is a way to output the content of this ByteArrayOutputStream to the PrintWriter. If anyone could give me a helping hand would be very much appreciated!

    Read the article

  • Localized text in Java

    - by Eager Learner
    My requirement is to display localized text messages in a J2EE web application. I know J2EE provides very good support for this. My question is what is the practice followed to have the localized messages stored to be used by the application. If I want to display Japanese / Chinese kind of messages which are not like English like char sets how do we get that messages/text into the properties files or Database tables.

    Read the article

  • [java] run 2 threads simultaneously

    - by lamsaitat
    hi all, in the case of an IM client. i have made 2 separate threads to handle sending packets (by std io) and receiving packets. the question is how to make these 2 threads run simultaneously so that i can keep prompting for input while at the same time be ready to receive packets at any time? i have already tried setting a timer but the data is always lost receiving.

    Read the article

  • Searching in a TreeMap (Java)

    - by Kronen
    I need to do a search in a map of maps and return the keys this element belong. I think this implementation is very slow, can you help me to optimize it?. I need to use TreeSet and I can't use contains because they use compareTo, and equals/compareTo pair are implemented in an incompatible way and I can't change that. (sorry my bad english) Map m = new TreeSet(); public String getKeys(Element element) { for(Entry e : m.entrySet()) { mapSubKey = e.getValue(); for(Entry e2 : mapSubKey.entrySet()) { setElements = e2.getValue(); for(Element elem : setElements) if(elem.equals(element)) return "Key: " + e.getKey() + " SubKey: " + e2.getKey(); } } }

    Read the article

  • Improving performance for WRITE operation on Oracle DB in Java

    - by Lucky
    I've a typical scenario & need to understand best possible way to handle this, so here it goes - I'm developing a solution that will retrieve data from a remote SOAP based web service & will then push this data to an Oracle database on network. Also, this will be a scheduled task that will execute every 15 minutes. I've event queues on remote service that contains the INSERT/UPDATE/DELETE operations that have been done since last retrieval, & once I retrieve the events for last 15 minutes, it again add events for next retrieval. Now, its just pushing data to Oracle so all my interactions are INSERT & UPDATE statements. There are around 60 tables on Oracle with some of them having 100+ columns. Moreover, for every 15 minutes cycle there would be around 60-70 Inserts, 100+ Updates & 10-20 Deletes. This will be an executable jar file that will terminate after operation & will again start on next 15 minutes cycle. So, I need to understand how should I handle WRITE operations (best practices) to improve performance for this application as whole ? Current Test Code (on every cycle) - Connects to remote service to get events. Creates a connection with DB (single connection object). Identifies the type of operation (INSERT/UPDATE/DELETE) & table on which it is done. After above, calls the respective method based on type of operation & table. Uses Preparedstatement with positional parameters, & retrieves each column value from remote service & assigns that to statement parameters. Commits the statement & returns to get event class to process next event. Above is repeated till all the retrieved events are processed after which program closes & then starts on next cycle & everything repeats again. Thanks for help !

    Read the article

  • Simple Java math operations

    - by user1730056
    I'm making a BMI calculator that doesn't seem to be working. The math operations work if i just do something like w/h, but once i had the brackets, it returns an error. If i change the variables w and h and use a constant number, the operation works. Another problem is that although i'm making result a double, it seems to be rounding to the nearest int. Could someone tell me what I'm doing wrong here? public class ass10 { public static void main(String[] args) { bmi(223,100); } public static bmi(int w, int h){ double result; result = (w/(h*h))*703 System.out.println(result) } }

    Read the article

  • Java Map question

    - by user552961
    I have one Map that contains some names and numbers Map<String,Integer> abc = new TreeMap<String,Integer>(); It works fine. I can put some values in it but when I call it in different class it gives me wrong order. For example: I putted abc.put("a",1); abc.put("b",5); abc.put("c",3); some time it returns the order (b,a,c) and some time (a,c,b). What is wrong with it? Is there any step that I am missing when I call this map?

    Read the article

  • Getting a java collection of objects in Alphabetical order

    - by MichaelMcCabe
    I have a question that I dont really know where to start. So I thought i'd ask it here. Basically, I have a drop down with names in it. I want these names to be in alphabetical order. Populating the drop down happens as follows; I query a database and pull down an Id and Name, make a object called "UserList", and set the name and id variables with what I get back. I then add this object to an ArrayList. I do this over and over. I then convert this collection to an array, and pass it to my JSP page using session.setAttribute("userList", UserList); I then populate the drop down as below. <c:forEach items="${usersCompanysList}" var="c" > There probably is a simple answer but how to I sort these names?

    Read the article

  • Sequence of the Events in Java

    - by ozlegolas
    Hi, I have two events for two seperate components, but there is a problem. JTabbedPane's stateChanged event is fired before JFormattedField's focusLost event. Is there a way of making stateChange event to be fired after focusLost event. Thanks, Tuna

    Read the article

  • Help making a button open another app with Java/Android

    - by user569503
    I am trying to learn to make a simple app that opens a couple of other apps to eliminate the need for another apps. I just can't figure it out. From reading here and other places it seems this should work. Button batteryhistory = (Button)findViewById(R.string.BatteryHistoryButtonDialog); batteryhistory.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent i = new Intent(); ComponentName n = new ComponentName("com.android.settings", "com.android.settings.BatteryHistory"); i.setComponent(n); startActivity(i); Thanks so much for the help :D

    Read the article

  • java/swing: font size selection + rendering

    - by Jason S
    I want to create and fill/stroke a path that consists of an outer boundary which is a square of side d and an inner boundary that is the outline of any of the capital letters. How can I do this? (challenges = creating a mask from a font, and figuring out the right size/position to use)

    Read the article

  • Executing in java code an external program that takes arguments

    - by rmaster
    Process p; String line; String path; String[] params = new String [3]; params[0] = "D:\\prog.exe"; params[1] = picA+".jpg"; params[2] = picB+".jpg"; try { p = Runtime.getRuntime().exec(params); BufferedReader input = new BufferedReader (new InputStreamReader(p.getInputStream())); while ((line = input.readLine()) != null) System.out.println(line); input.close(); } catch (IOException e) {System.out.println(" procccess not read"+e);} i don't get any error, just nothing in cmd.exe prog.exe is working fine What to improve in order to make this code working?

    Read the article

  • Java ThreadPool for multiple identical tasks

    - by tdimmig
    I have 1 thread who sole job is to grab DatagramPackets off of a socket and stick them in a buffer. Another thread works out of that buffer, processing the DatagramPackets. I'd like to have a pool of threads working out of that buffer. I had thought to use a fixed thread pool to do this. To do so, do I need to create the pool, then submit enough runnables for execution to fill it up? I had hoped for a way to say "this is the thread/runnable that I want you to execute, this is how many I want running, GO!". Is there such a method of doing this? Is something other than a fixed thread pool better suited?

    Read the article

  • Java iterative vs recursive

    - by user1389813
    Can anyone explain why the following recursive method is faster than the iterative one (Both are doing it string concatenation) ? Isn't the iterative approach suppose to beat up the recursive one ? plus each recursive call adds a new layer on top of the stack which can be very space inefficient. private static void string_concat(StringBuilder sb, int count){ if(count >= 9999) return; string_concat(sb.append(count), count+1); } public static void main(String [] arg){ long s = System.currentTimeMillis(); StringBuilder sb = new StringBuilder(); for(int i = 0; i < 9999; i++){ sb.append(i); } System.out.println(System.currentTimeMillis()-s); s = System.currentTimeMillis(); string_concat(new StringBuilder(),0); System.out.println(System.currentTimeMillis()-s); } I ran the program multiple time, and the recursive one always ends up 3-4 times faster than the iterative one. What could be the main reason there that is causing the iterative one slower ?

    Read the article

  • Catching TransactionRolledbackLocalException in Java

    - by user271858
    I receive javax.ejb.TransactionRolledbackLocalException in Websphere 7 from the container and I wonder how is it possible to catch this exception? I have a timeout set in Websphere and get this message after this time. I run session beans. I am trying to find what SQl statement was the cause of this exception. Where can i find that?

    Read the article

  • [Processing/Java]Visibility/Layering Issue

    - by nnash
    I'm working on a small sketch in processing where I am making a "clock" using the time functions and drawing ellipses across the canvas based on milliseconds, seconds and minutes. I'm using a for loop to draw all of the ellipses and each for loop is inside its own method. I'm calling each of these methods in the draw function. However for some reason only the first method that is called is being drawn, when ideally I would like to have them all being visibly rendered. //setup program void setup() { size(800, 600); frameRate(30); background(#eeeeee); smooth(); } void draw(){ milliParticles(); secParticles(); minParticles(); } //time based particles void milliParticles(){ for(int i = int(millis()); i >= 0; i++) { ellipse(random(800), random(600), 5, 5 ); fill(255); } } void secParticles() { for(int i = int(second()); i >= 0; i++) { fill(0); ellipse(random(800), random(600), 10, 10 ); background(#eeeeee); } } void minParticles(){ for(int i = int(minute()); i >= 0; i++) { fill(50); ellipse(random(800), random(600), 20, 20 ); } }

    Read the article

  • Container of Generic Types in java

    - by Cyker
    I have a generic class Foo<T> and parameterized types Foo<String> and Foo<Integer>. Now I want to put different parameterized types into a single ArrayList. What is the correct way of doing this? Candidate 1: public class MMM { public static void main(String[] args) { Foo<String> fooString = new Foo<String>(); Foo<Integer> fooInteger = new Foo<Integer>(); ArrayList<Foo<?> > list = new ArrayList<Foo<?> >(); list.add(fooString); list.add(fooInteger); for (Foo<?> foo : list) { // Do something on foo. } } } class Foo<T> {} Candidate 2: public class MMM { public static void main(String[] args) { Foo<String> fooString = new Foo<String>(); Foo<Integer> fooInteger = new Foo<Integer>(); ArrayList<Foo> list = new ArrayList<Foo>(); list.add(fooString); list.add(fooInteger); for (Foo foo : list) { // Do something on foo. } } } class Foo<T> {} In a word, it is related to the difference between Foo<?> and the raw type Foo. Update: Grep What is the difference between the unbounded wildcard parameterized type and the raw type? on this link may be helpful.

    Read the article

< Previous Page | 327 328 329 330 331 332 333 334 335 336 337 338  | Next Page >